Low-FODMAP diets have been used as nutrition therapy for sufferers of Irritable Bowel Syndrome for years. But some experts see these fermentable carbohydrates behind a number of contemporary digestive woes, including gluten intolerance.

Extraction by putrefaction has a certain ring to it. A ring that will have older consumers recalling the gagging flavor of their grandmother’s cod liver oil. Allowing vats of discarded cod livers to rot and thereby separate from their fat, however...